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Dynamic decision making' describes the practice of anaesthesia more than any other single characteristic - and anaesthesia is characterised by dynamic decision making more than any other medical speciality. The typical surgical case requires the anaesthetist or anesthesiologist to make hundreds of decisions, modified to suit the evolving environment of the case. Each decision itself modifies the patient context, creating a multiverse of decision and outcome possibilities.

"No plan survives contact with the [surgeon and patient] – Helmuth von Moltke

These decisions add up. Big and small, decision after decision over the day leads to a measurable fall in the quality of our decisions by the final case. Psychologists describe this as 'ego depletion', colloquially called 'decision fatigue'.¹

Though not yet widely appreciated in medicine (though it is gaining traction on the medical front-line²), decision fatigue has been identified in many decision-focused professions. Decision fatigue has been identified in judges ruling on cases, with parole decisions made later in the day being of 'lesser quality' and having lower rates of parole than those at the start of the day (10% vs 70% for the first case of the day heard).³

"We find that the percentage of favorable rulings drops gradually from ~65% to nearly zero within each decision session and returns abruptly to ~65% after a break."

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Does sugammadex mean the end of suxamethonium for rapid sequence induction?

The answer: No, not by a long shot. Let me explain...

Suxamethonium (succinylcholine) is a depolarising muscle relaxant and often the first choice for muscle paralysis when a rapid sequence induction (RSI)¹ is needed. In addition to working quickly suxamethonium has a very rapid offset. For both anaesthetist and patient these are very desirable characteristics, although they come at a price. The price is suxamethonium's long list of side effects, ranging from minor to life threatening.² Were it not for it's life-saving fast-kinetics, suxamethonium's use in modern anaesthesia would no longer be justifiable.

Enter rocuronium

When rocuronium was first introduced in the 1990s it was met with excitement.³ Rocuronium's claim to fame was a very fast onset of action. Because it was less potent than other non-depolarising muscle relaxants of its generation (atracurium & vecuronium) a larger dose was required to achieve the same level of muscle paralysis. This dose created a large concentration gradient between plasma and the neuromuscular junction resulting in a faster onset of action. By giving a very large dose of rocuronium the anaesthetist could produce acceptable intubating conditions within 60 seconds, creation the first reliable modified rapid sequence induction.

Unfortunately the result of using such a large dose of rocuronium is a prolonged blockade. Even at lower doses (0.6 mg/kg 2x ED95) rocuronium produces a block that lasts at least five times longer than suxamethonium. At the 1.2 mg/kg (4x ED95) modified-RSI-dose of rocuronium the block duration stretches out even longer, reaching the duration of pancuronium. In the event of being unable to intubate, or worse unable to ventilate, prolonged blockade is disastrous. At this point rocuronium only provided half a solution for the replacement of suxamethonium.

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A great way to capture and share knowledge gleaned from the evidence is with...

You may have noticed that suggested articles arriving in your emailed metajournal or appearing in online article lists have a pearl or summary above the abstract. My aim is to make keeping up to date and understanding the current literature even more time efficient.

You can add your own notes to any article or abstract you read — both to help you capture the most actionable 'take-away' message, and also to share your wisdom with others. Simple scroll down below the article abstract to find a list of notes and a text-box for you to add your own.

Notes can be either pearls, summaries or comments, depending on the type of information you want to share.

Two examples of articles with notes to get you started:

• The 2008 POISE study: Effects of extended-release metoprolol succinate in patients undergoing non-cardiac surgery.
• Fink & Hollman's 2012 'Myths and facts in neuromuscular pharmacology'.

Jump in and share your wisdom!

Sugammadex (Bridion®) is a remarkable drug. It also has a cool name. The anaesthesia community has moved very quickly to embrace the potential of this first and only 'selective relaxant binding agent' (SRBA), despite it's considerable cost.

"Sugammadex is likely the most exciting drug in clinical neuromuscular pharmacology since the introduction of atracurium and vecuronium in the middle 1980s." - Miller RD ¹

Novel pharmacology and a cool name are however insufficient reasons alone to alter our practice. There is a certain lack of clarity in the community and literature as to where sugammadex fits into anaesthesia practice and to what extent it should alter how we currently manage muscle relaxation and reversal. There has also been very limited discussion of the unintended consequences of a shift to rocuronium-sugammadex based techniques over other neuromuscular drugs.

There is no doubt that sugammadex offers a new and improved way of reversing aminosteroid muscle relaxation, in particular that from rocuronium.  The speed at which it reverses even profound neuromuscular blockade is incredible and potentially life saving. Sugammadex‘s onset is 10 times faster than neostigmine and three times faster than edrophonium.²

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The rise of sugammadex has lead me down a path looking into wider aspects of my own neuromuscular blocking drug (NMBD) use. The evidence for NMBD use, monitoring and reversal is interesting, both for how consistently the same messages have been repeated over the past three decades – and for how little we have improved our practice in spite of mounting evidence demanding that we should.¹

I need to do better and you probably also need to do better with how we manage NMBDs.

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